Father Used a Signal Jammer to Keep His Kids Offline Now Faces Jail Time (hothardware.com)

he jammed neighbour's security system.

Using any kind of signal jammer is a crime in the UK. It wouldn't surprise me for it to be a crime in France.

See https://www.ofcom.org.uk/spectrum/interference-enforcement/s... for example

"It is a crime to use any apparatus, including jammers, for the purposes of deliberately interfering with wireless telegraphy (radio communications) in the UK. The maximum penalty is two years’ imprisonment and/or an unlimited fine. See section 68 of the Wireless Telegraphy Act 2006."

Ofcom is the UK's communications regulator.

If it impairs access to emergency services it is a serious matter.

I assume it only started at midnight so he could use his phone. Ironic.