unconstitutionally
🇺🇸
/ˌʌnˌkɑːnstɪˈtuːʃənəli/
🇬🇧
/ˌʌnˌkɒnstɪˈtjuːʃənəli/
Contrary to the principles of a constitution.
The new law was declared to be passed unconstitutionally, and it was struck down by the court.