MA Police Civil Service cheat sheet

A verb agrees with its subject in number; prepositional phrases between them (e.g., 'the box of files') do not change the verb.

Compound subjects joined by 'and' take a plural verb; subjects joined by 'or'/'nor' take a verb matching the nearer subject.

Use subject pronouns (I, he, she, they, who) for subjects and subject complements; object pronouns (me, him, her, them, whom) after verbs and prepositions.

'Its' is possessive, 'it's' means 'it is'; 'their' is possessive, 'there' is place, 'they're' means 'they are'.

A comma alone cannot join two independent clauses; use a period, semicolon, or a comma plus a coordinating conjunction (and, but, or, nor, for, so, yet).

A semicolon links two closely related independent clauses; a colon follows a complete clause and introduces a list, example, or explanation.

Lists and comparisons must be parallel: all nouns, all gerunds (-ing forms), or all infinitives (to + verb).

Place modifiers next to the word they modify; a dangling modifier has no logical word in the sentence to attach to.

Singular possessive adds 's; plural possessive ending in s adds only the apostrophe (an officer's report, the officers' reports).

Main idea = topic + the author's central point; it is broader than any single detail and often appears in the first or last sentence.

Test each answer against the passage: an option is wrong if it is unsupported, only partly supported, or contradicts the text.

An inference must be a small, defensible step beyond the text - not a guess and not outside knowledge.

Signal words: 'first, next, finally' = sequence; 'because, therefore, as a result' = cause-effect; 'however, similarly, unlike' = comparison or contrast.

Scope rule: eliminate choices that are too broad, too narrow, or off-topic even when the statement itself is factually true.

Tone is revealed by word choice; identify whether the author is neutral, critical, approving, or doubtful.

Vocabulary in context: substitute each option into the original sentence and check that the surrounding words still make sense.

For 'author's purpose' questions, choose among inform/explain, persuade, and entertain based on the passage's structure and language.

Recall improves with focused attention at encoding; divided attention during an event reduces later accuracy.

Weapon focus: a witness fixated on a weapon typically recalls fewer facial and clothing details.

Serial position effect: first and last items in a series or lineup are recalled better than middle items.

High stress narrows attention to central details (the threat) and impairs peripheral detail such as bystanders and background.

Eyewitness confidence is a weak predictor of accuracy; do not treat certainty as proof.

Memory is reconstructive; post-event information from other witnesses, media, or questioning can alter recall.

Standard descriptive sequence: top to bottom (head, face, build, clothing), then vehicle (make, color, plate, direction of travel).

Chunking groups items into meaningful units (e.g., a plate as 3-ABC-123) so more can be held in short-term memory.

Estimator variables (lighting, distance, duration, stress) are fixed at the scene; system variables (lineup procedure, questioning) are controllable.

Valid deductive forms: If A then B; A; therefore B (modus ponens). Also: If A then B; not B; therefore not A (modus tollens).

Invalid forms: affirming the consequent (If A then B; B; therefore A) and denying the antecedent (If A then B; not A; therefore not B).

The contrapositive of 'If A then B' is 'If not B then not A' and is logically equivalent; the converse 'If B then A' is not.

A sufficient condition guarantees the outcome; a necessary condition is required but does not guarantee it.

In syllogisms, 'all A are B' plus 'all B are C' yields 'all A are C'; 'some' statements cannot support a universal conclusion.

Correlation does not establish causation; look for a third variable or a reversed direction of influence.

An assumption is an unstated premise the argument needs; negation test - if negating it breaks the argument, it is an assumption.

For ordering and scheduling problems, draw a diagram, fix the absolute constraints first, and eliminate options that violate any rule.

Check answers by working backward from the choices, especially in numeric or ranking problems.

Priority order: officer and public safety, then containment and control, then investigation and documentation.

Procedural justice has four elements: voice, neutrality, respect, and trustworthy motives.

De-escalation uses time, distance, cover, and communication, and is used when feasible before force escalates.

Force must be objectively reasonable, proportional to the threat, and reduced as the threat decreases.

Report misconduct up the chain of command; witnessing excessive force creates a duty to intervene and to report.

Never compromise integrity: no false statements, no falsified reports, no gratuities that create an obligation.

Confidential information is shared only on a need-to-know basis, not with family, media, or other agencies without authorization.

Active listening: paraphrase, ask open questions, acknowledge emotion, and avoid interrupting.

Document objectively: record observable facts and quoted statements rather than conclusions about a person's character.

Distance = rate × time; rate = distance ÷ time; time = distance ÷ rate.

Percent change = (new value − old value) ÷ old value × 100.

Average (mean) = sum of values ÷ number of values; median = middle value of the ordered data.

Ratios scale by multiplying both terms by the same factor; set up a proportion a/b = c/d and cross-multiply.

Convert units before calculating: 1 mile = 5,280 feet; 1 hour = 60 minutes; 1 kilogram ≈ 2.2 pounds.

Probability = favorable outcomes ÷ total outcomes; values range from 0 to 1 and sum to 1 across all outcomes.

In tables, read row and column headings and units first, and confirm whether figures are totals or subsets before computing.

Area of a rectangle = length × width; area of a triangle = ½ × base × height; perimeter = sum of all sides.

Estimate before computing: round to nearby numbers to catch misplaced decimals.

By convention north is at the top of a map; verify with the compass rose before assuming.

Bearing is measured clockwise from north: N = 0°/360°, E = 90°, S = 180°, W = 270°.

Grid references read easting (horizontal, along the bottom) first, then northing (vertical, along the side).

Scale factor: real distance = measured map distance × scale (e.g., 2.5 in × 1 mi per in = 2.5 mi).

Turns: a right turn from north heads east; a left turn from north heads west; a 180° turn reverses direction.

When facing a direction, left and right are relative to that facing, not to the edges of the page.

Contour lines close together indicate steep terrain; widely spaced lines indicate a gentle slope.

A route is retraced by reversing the sequence of steps and swapping left for right.

Clock-face directions: 12 = ahead, 3 = right, 6 = behind, 9 = left.