In the letter, her lawyers said: "That appears to be wholly disproportionate and unjustified having regard to the Twitter material itself and the broader circumstances of the case."
They said Paris, from Sheerness, was visited by a Special Branch officer at her home on April 11, along with a second officer, and asked to surrender her mobile for examination.
Then she was requested to attend an interview under caution on April 14.
She was quizzed for one hour and seven minutes about material posted on her Twitter account which had already been published in the media. Her phone was returned three days later.
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Holly has your forecast.
Hopes may be fading for little Lucas Dobson. But crowds have been offering prayers and lighting candles for the six-year-old in Sandwich.
Police officers have paid silent tributes to their colleague, PC Andrew Harper. Flowers continue to arrive at the roadside where he died.