The following are excerpts from the "Summary Offences and Law Enforcement Legislation Amendment (Laser Pointers) Bill of 2008". The full text is here. In addition, there is a summary with some additional interpretation by the Newcastle Astronomical society on this webpage.

An Act to amend the Summary Offences Act 1988 to make it an offence to possess or use a laser pointer in a public place, to amend the Law Enforcement (Powers and Responsibilities) Act 2002 to include a laser pointer as a dangerous implement within the meaning of that Act; and for other purposes.

[EXCERPTS]

[2] Section 3 (1), definition of "dangerous implement"
    Insert after paragraph (d):
            (e) a laser pointer,

[3] Section 3 (1)
    Insert in alphabetical order: laser pointer means a hand-held battery-operated device, designed or adapted to emit a laser beam, that may be used for the purposes of aiming, targeting or pointing.

[4] Sections 26 (1) and (3) and 87 (a)
    Insert "(other than a laser pointer)" after "dangerous implement" wherever occurring.

[5] Section 26 (1A)
    Insert after section 26 (1):
        (1A) A police officer may request a person who is in a public place to submit to a frisk search if the police officer suspects on reasonable grounds that the person has a laser pointer in his or her custody.

Subdivision 2 Laser pointers
    11FA Custody or use of laser pointer in public place
        (1) A person must not, without reasonable excuse (proof of which lies on the person):
                (a) have in his or her custody a laser pointer in a public place,
                or
                (b) use a laser pointer in a public place.
                 Maximum penalty: 50 penalty units or imprisonment for 2 years, or both.

        (2) Without limitation, it is a reasonable excuse for the purposes of this section for a person:
                (a) to have custody of, or use, a laser pointer if the custody or use is reasonably necessary in all the circumstances for the lawful pursuit of the person's occupation, education, training or hobby, or
                (b) to have custody of a laser pointer if the person has custody during travel to or from or incidental to that occupation, education, training or hobby.

        (3) The regulations may provide that this section does not apply to or in relation to any specified class or description of laser pointer.

        (4) In this section: Laser pointer means a hand-held battery-operated device, designed or adapted to emit a laser beam, that may be used for the purposes of aiming, targeting or pointing.

Section 7.41(1) of Part I of the Canadian Aeronautics Act is a general prohibition against behavior that endangers aircraft:

Prohibition — unruly or dangerous behaviour

7.41 (1) No person shall engage in any behaviour that endangers the safety or security of an aircraft in flight or of persons on board an aircraft in flight by intentionally

• (a) interfering with the performance of the duties of any crew member;
• (b) lessening the ability of any crew member to perform that crew member's duties; or
• (c) interfering with any person who is following the instructions of a crew member.

Punishment

(2) Every person who commits an offence under subsection (1) is liable

• (a) on conviction on indictment, to a fine of not more than $100,000 or to imprisonment for a term of not more than five years, or to both; and
• (b) on summary conviction, to a fine of not more than $25,000 or to imprisonment for a term of not more than eighteen months, or to both.

Deeming — "in flight"

(3) For the purpose of subsection (1), an aircraft is deemed to be in flight from the time when all external doors are closed following embarkation until the time at which any external door is opened for the purpose of disembarkation.

This FAQ page from the Health and Safety Executive gives some information about laser pointer guidance in the U.K.